Railway-crossing signal switch



May 22, 1928. 1,670,854

R. L. GRAY ET AL RAILWAY CROSSING SIGNAL SWITCH Filed Aug. 15, 1927 4 John F FuI'maTL 1 WW: 1 x

Patented May 22, 1928.

- UNITED STATES PATENT OFFICE.

301mm L. GRAY AND JOHN F. FURMAN, or PORTSMOUTH, VIRGINIA.

RAILWAY-CROSSING SIGNAL SWITCH.

Application filed August'15, 1927. Serial No. 213,152.

The present invent-ion relates primarily to railway crossing signal apparatus and the primary object of the invention is to provide an improved circuit closing device operable automatically by the railway rolliug stool: for completing a circuit thru signaling apparatusdisposed at'a remote location lroni the circuit closing d'eviceand preferably at" a. road. crossing for signaling to trafiic and warningof an approaching train. I v

A further object of the invention is to provide an improved railway crossing signal switch of compact and durable construction for mounting upon one of the rails of the railway in a manner whereby the signal Wlll be alternately operated upon passage of each wheel of the rolling stock over the switch mechanism.

A further object of the invention is to provide a novel and improved circuit closing means for railway crossing signals embodying a pair of co-acting circuit closing contacts so operable upon passage of rolling stock along the rail as to insure positive contacting of the contacts of each pair in a manner for insuring positive operation of a warning signal. A

A still further and important object of the invention is to provide an improved railway crossing signal switch embodying fixed and movable contact members which are intended to be secured directly to one of the rails in such co-related manner as to eliminate the necessity of providing further mounting means for the contacts and thus materially sim'plifyingand reducing the'cost of installation of the signal controlling switch.

A still further object of the invention is to provide an improved signal controlling switch for railway crossings embodying an arrangement whereby unauthorized operation of the signal as by bridging of certain of the conductor wires will be reduced to a minimum.

Other objects and advantages of the invention will be apparent duringthe course of the following detailed description, taken in connection with the accompanying drawing forming a part of this specification and in which drawing: I

Figure l is a fragmentary side elevation of a conventional type of railway rail and showing the improved signal controlling switch as mounted thereon and in its nonrail.

circuit closing position, said view showing the protective covering broken away for disclosing the particular mounting of the switch elements.

Figure 2 is a vertical section on line'22 of Figure Figure 3 is a view substantially similar to that shown in Figure 1 and showing the switch as having been operated byja wheel of the rolling stock.

Figure 4 is an enlarged fragmentary section on line 44 of Figure 3.

Figure 5 is an enlargedfragmentary section on line 55 of Figure 1 and illustrating the manner in which the yieldable contaclt arm is insulatively mounted upon the rar Figure 6 is an enlarged fragmentary section on line 6,-6 of Figure 3 and showing the manner in which one of the stationary contacts are insulatively mounted upon the Figure 7 is a diagrammatic view illustrating one method of wiring between the switch and a visual signal. I

Figure 8 is awi'ring diagram showing the manner inwhich both audible and visual signals may be controlled by the circuit controlling switch.

Referring to the drawing'in detail, and wherein similar reference characters designate corresponding parts thruout the several views, the letter A designates a conventional type of railway rail, and B the improved circuit controlling device associated with the rail A for automatic control of a signal C preferably disposed at a remote location from the circuit controlling means B.

The rail A which is of ordinary construction embodies a tread or head 5'upon the upper surface of which the rolling stock ioves, a vertically disposed web portion 6, and the usual base flange 7 which is intended to rest upon the usual cross ties or sleepers. As will be observed with the shown, the tread 5 projects to each side of the vertical web 6 and forms an underlying face at each sideof the upper portion of the web. The numeralD may designate one wheel of a railway car or any other rolling stock for movement along the rail A.

Mounted in spaced apart relation lon itudiually of the rail A and upon one si e of the web 6 at a point substantially midway of its height. is a pair of stationary contact blocks 8 and 9 which are preferably of type of rail identical construction and are preferably formed of copper. Each of the stationary contact blocks 8 and 9 is provided adjacent one end'with a thru and thru bore 10 in which is positioned a suitable insulating bushing ll for receiving an attaching cap screw or bolt 12. The terminal portion of the shank of the fastening element 12' is threaded as at 13 for threading into a drilled and tap bore 14 provided in one face of the web 6. Suitable insulating strips 15 are arranged at the inner side of each of the con tact blocks 8 and 9 for insulatively keeping the blocks from metallic contact with a rail A, and an insulating Washer 15 is preferably disposed at the outer end of the bore 10 for keeping the head of the fastening elements 12 from contact with the blocks. By observing Figure (5 and wherein. is shown a detail sectional view illustrating the manner of attachment of the stationary contact blocks to the rail A, it will be seen that the blocks are insulatively isolated from elec trical connection with the web {3 and that the only requisite procedure required for mounting of the blocks is that of drilling and tapping the bores let on one face of the rail web. A tapped bore 16 is provided in each of the blocks 8 and 9 acent the opposite ends of the blocks from which the bores 10 are formed, and these bores 16 are intended to receive threaded terminal elements or screws 17 for electrical connection of one terminal of conductor wires 18 and 19 to the stationary contact blocks 8 and 9 respectively. It is preferred that the stationary contact blocks 8 and 9 be mounted on the web 6 at a substantial distance apart for a purpose to be subsequently set forth.

Mounted to extend longitudinally of the rail A in spaced relation above the hori- Zontally disposed stationary contact blocks 8 and 9, is a spring contact mounting arm 20 This mounting arm 20 is preferably formed from an elongated strip of spring material tempered to provide suitable resiliency and twisted intermediate its ends as at 21 fora one-quarter turn for providing an attaching portion 22 and a free contact carrying portion 23. This contact mounting arm 20 which. is intended to be mounted at the same side of the web 6 as that upon which the stationary contact blocks 8 and 9 are mounted, is preferably secured tov the web as by means of [a suitable number of fastening elements 24: preferably in the form of cap screws having engagementin tapped bores 25 formed in the web 6 longitudinally thereof and spaced to one side of the contact blocks 8 and 9. These fastening elements 24 extend thru the attaching portion 22 so that the attaching portion extends parallel with the base of the web 6., while the free contact carrying portion 23 has its major cross sectional dimension disposed in a plane at a right angle to the base of the web and out of contact with the web. Suitable insulating strips and bushings as designated generally by the numeral 26, may be employed for insulatively retaining the mounting arm 20 out of electrical contact with the metallic rail A. The mounting arm 20 when secured longitudinally of the rail has its free contact carrying portion 28 extending in parallel spaced relation above both of the stationary contacts 8 and 9between the contacts and one underlying face of the railhead 5 the underlying face of the rail head being designated by the numeral 27 in Figure 2.

Mounted in spaced relation longitudinally i of the free contact carrying portion 23 is a pair of co-acting contacts 28 and 29 which co-act respectively in in circuit closing relation with the stationary contact blocks 8 and 9. These co-acting contacts 28 and 29 may be secured to the free portion 23 in any suitable manner and in the example shown are connected to the underside thereofas by means of suitable cap screws 30 which pass thru the contact carrying portion 23 and have threaded engagement with the respective contacts 28 and 29. Suitable insulating members 31 are provided for electrically isolating the contacts 28 and 29 from the portion 23 and also from one another. Each of the contacts 28 and 29 are preferably provided with tapped bores for threaded reception of suitable terminal screws 32 whereby one terminal of electrical conductors and 34 may be electrically connected respectively with the contacts 28 and 29. By observing Figures'l and 2 it will be seen that upon depressing ing portion 23, that the contact 28 will be moved into electrical contact with the contact block 8, and the contact 29 moved into electrical contact with the stationary contact block9 so that independent circuits are com pleted by each set of co-acting contacts and stationary contact blocksj Mounted for vertical movement in a vertically formed guide way 30 provided in the overhanging portion of the rail head 5 at a point midway between the mounting of the contact blocks 8 and 9, is an operating,

the free contact carryllri pin 'or plunger 32 which is'preferably formed 'of a non-corroding metal such as Monel metal. This vertically movable pin or plunger 32 is preferably of cylindrical formation and is provided intermediate its ends with a stop collar 33 which engages the underlying face 27 of the rail head'in a manner for limiting upward movement of the pinthru the guide way 30. As will be ob served, the lower end of the pin 32 is intended to rest freely upon the upper face of the free contact carrying portion 23 at a point midway between. the contacts 28 and 29- An insulating bushing such as fiber or the like, and as designated at 34', is preferably disposed in the guide way for act-' mg as a wear bushing and also as an insulating means for the vertically movable operating pin. That portion of the pin 32 above the stop 33 is of such length that when the stop engages the underlying face 27, the upper rounded end of the pin will project slightly above the upper surface of the tread 5 so'that when the pin is engaged by the wheel D of the rollingstock, the pin will be depressed for moving the free portion 23 of the mounting arm 20 downwardly so that the CODtZLCtSQS and 29 engage respectively with the stationary contact blocks 8 and 9.

The object in so spacing the co-acting contacts a substantial distance apart is to permit of the free contact carrying portion 23 to be flexed in a manner as illustrated in Figure 3 when forced downwardly by the pin '32 and thus insure positive engagement of the contact 28 with the contact 8 and the contact 29 with its companion contact 9. This yielding of the portion 23 will be found extremely desirable since during installation of the device it is apt to occur that the stationary contact blocks 8 and 9 may not be mounted in perfect parallel alignment with the longitudinal center; of the free contact carrying portion 23.

A protecting casing 40 is preferably pro vided for enclosing the switch structure, and this casing embodies a face portion 41 of a height to engage at its upper edge the rail tread 5 and at its lower edge of the upper surface of the base flange 7. Each end of the casing is closed by end walls 42 the free edges of which are intended to engage the face of the web 6. The casing 40 is preferably secured in position as by means of threaded fastening elements 44 which extend thru the flange 45 at the lower edge of the casing and are threaded into the rail base flange 7 as illustrated in Figure 2.

Connected'with and opening inwardly of the casing or cover 40 at one of the end walls 42, is a suitable conduit 46 thru which the conductor wires are led for connection with the various contacts of the switch structure. This conduit 46 may continue along the railroad and lead to any suitable signaling device intended to be operated by the switch structure B; It is preferred, however, that the conduit 46 lead to a suitable crossing signal located at a remote point along the railway from which the switch structure is mounted.

Referring to the wiring diagram in Figure 7, and wherein is shown one manner of use of the switch device for automatic control of a remote signal device C, the lead wires 33 and 34 from the contacts 28 and 29 are shown connected with opposite poles of a.

suitable source of electrical energy 50. With this circuit arrangement it will be seen that when the co-acting sets of contacts 8 and 28 and 9 and 29, are moved into engagement with one another that an electrical circuit will be completed for operating the visual signal structureG, and that it is necessary that each of the co-acting sets of contacts be moved into electrical contact with one another for completing a circuit to the signal C. The'source of electrical energy 50 is preferably connected as close as possible with the switch structure B, so that there is little likelihood of a person being able to actuate the' signal by "endeavoring to bridge the conductors 18 and 33 and 19 and 34. It will also be observed in F igure 7 that a bridging of the conductors 18 and 19 will not cause a circuit to be completed to the signal C. If so desired, the conductor wires after passing from the protective cover 40 may lead off in opposite directions for preventing operation of the signal by an unauthorized person, by bridging certain of completing a circuit thru the visual signal C while the contacts 9 and 29 may serve to complete a circuit thru the conductors 61 and 62 of a branch circuit leading to the audible signal 60. A transformer 64 may be employed for reducing the current to the audible signal 60 which in the example shown is in the form of a bell which may be operated on a considerably lower voltage than that required for illumination of the visual signal-C. A switch 65 may be disposed in the circuit leading to the signal C so that if desired the visual signal may be rendered. inoperative during daylight and allowingonly the audible signal to be operated by the switch structure. Thus it will be seen that with the arrangement as illustrated in Figure 8, that each set of co-acting contacts act to complete an independent circuit for independent operation of'both audible and visual signals.

From the foregoing description "it will be apparent that a novel and improved automatic circuit controlling switch structure for railway signals has been provided which is of extremely simple and durable construc tion, and which switch device is devoid of any mounting structure, and is intended to have the various elements thereof mounted directly upon the rail in a protected position and at a location to be operated by rolling stock moving over the rail.

Changes in detail may be made to the specific form of the invention herein shown and described, without departing from the spirit of the invention or the scope of the following claims.

We claim: r

1. In acontrol switch for railway signals including an electric circuit, the. combination with a railway rail, of a pair of contact members fixedly mounted in'spaced re lation upon the rail and connected in said electric circuit, a yieldable arm carried by v the rail and having a tree portion spanning the fixed contacts and normally spaced there: from, a co-acting contact element carried by said tree portion of the arm for each of the fixed contact members and connected in said electric circuit, and means engageable by the wheels of rolling stock on the rail for imparting movement to said arm and moving said contactsinto circuit completing relation. 2. In a control switch for railway signals including an electric circuit, the con'ibination with a railway rail, of a pair of contact blocks .lixedly mounted in spaced relation upon the web portion of the rail andtconnected in said electric circuit, ayieldable contact arm mounted upon the web of the rail and having a tree portion spanning the tixed contacts but normally spaced therefrom, a co-acting contact element carried by said tree portion of the arm for each of the tixed contact blocks and connected in said electric circuit, and means acting upon the tree portion oil? said arm intermediate said contact elen'ients and engageable by the wheels of rolling stock on the rails for imparting movement to said arm and moving said contacts into circuit completing relation. 3. In a control switch for railway signals including an electric circuit, the combination with a railway rail, of a pair of contact blocks insulatively mounted in spaced relatioi'i longitudinally of the web portion ot the rail and connected in said electric circuit, an arm rigidly mounted on the web portion of the rail and having a yieldable tree portion extending longitudinal ly ot the rail above the hired conlact'bhmks and normally spaced llhGl'Qfl'Ol'I'l, a pair otco-acting contact" elements insulatively mounted in spaced relation upon the yieldable free end portion of the arm tor engagen'ient one with each of said contact blocks and connected in said electric circuit and a pin vertically movable in the rail above the yieldable "free end portion of the arm and engageable by the wheels of rolling stock on the rail tor imparting moven'ient to the arm and moving said contacts into circuit closing relation.

' l. in a control switch for railway signals including an electric circuit, the con'ibination with a. railway rail including a head, a base l'langc and a web, of a pair of contact blocks insulatively mounted in spaced relation longitudinally of the rail upon said web, a spring arm mounted. upon the web and having ayieldable free end portion extending longitudinally of the rail in normally spaced relation above the contact blocks, co-acting contact elements insnlatively carried by the yieldable free end portion of the arm foreach of said contact blocks, and a plunger mounted or vertical movement in the railhead to one side ot the web and having it lower end engaging the tree portion of the arm intermediate the contact elements carried thereby.

5. in a control switch for railway signals inclluling an electric circuit, the combination with a railway rail including a head, a base flange and a web, of a pair of contact blocks insulatively mounted in spaced relation longitudinally ot the rail upon said web, a spring arinmounted upon the weband having a yieldable "tree end portion extending longitudinally of the rail in normally spaced relation above the contact blocks, co-acting contact elements insulatively carried by the under side oi? the yieldable free end portion ot the army and spaced to engage one with each ot said contact blocks, and a pin mounted tor vertical movement in the rail head to one side 01 the web and having its lower end engaging the tree portion of the arm midway ol' the contact elements carried thereby, said pin being of a length to normally project above the tread surface oi the rail head and when depressedby the \vheels of rolling stockon the rail tocause the tree end portion of said spring arm to he a tiered down wardly between the contact elements after engagen'ient with the fixed contact blocks. i

(3. In a control switch for railway signals including an electric circuit,the combination with a railway rail including a head, a base tlange and a web, of a pair of contact blocks insulatively,mounted in spaced relation longitudinally oi the rail upon said web, a spring arm mounted upon the web and having a yieldable free end portion extending longitudinally of the rail in normally spaced relation above the contact blocks, a pin mounted for vertical movement in the rails head and resting freely at its lower end upon the upper side of the yield able tree end portion of the spring arm, said arm acting to normally retain the upper end ol the pin projecting above the tread surface of the rail head, and contact elemen'ts carried by the free end portion of the arm to each side of the vertically movable pin i'or engagement one with each of said lixed contact'blocks upon depression of the pin by the wheels of rolling stock moving on. the rail. i

7. In a control switch for railway signals including an electric circuit, the, combination with a railway rail including a head, a base flange and a web, ot a pair of contact blocks insulatively mounted in spaced relation longitudinally of the rail upon said web, a. yieldable arm mounted upon the rail web and having a free end portion disposed above the fixed contact blocks and normally tion engaging at itsupper edge the rail spaced therefrom, a co-acting element carhead and at its lower edge the rail flange, ried by said free portion of the arm for and end Walls extending inwardly upon the each of the fixed contact members and conface portion to engagement with the rail nected in said electric circuit, a plunger Web, and means for removably securing the 15 mounted for vertical movement in the rail cover at its lower portion to the base flange head and engageable with the free end porof the rail.

tion of the arm between the contact elements 7 carried thereby, and a protective cover for ROBERT L. GRAY.

l0 said switch structure including a face por- JOHN F. FURMAN. 

